StackOverflow2013

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POStop drawing of CATiledLayer
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copied!<p>Is is possible to stop <code>CATiledLayer</code> to draw (drawLayer:inContext)? It draws asynchronously and when i try to release CGPDFDocumentRef, which is used by <code>CATiledLayer</code>, the app crashes (EXC_BAD_ACCESS).</p> <p>That's my view:</p> <pre><code>@implementation TiledPDFView - (id)initWithFrame:(CGRect)frame andScale:(CGFloat)scale{ if ((self = [super initWithFrame:frame])) { CATiledLayer *tiledLayer = (CATiledLayer *)[self layer]; tiledLayer.levelsOfDetail = 4; tiledLayer.levelsOfDetailBias = 4; tiledLayer.tileSize = CGSizeMake(512.0, 512.0); myScale = scale; } return self; } // Set the layer's class to be CATiledLayer. + (Class)layerClass { return [CATiledLayer class]; } - (void)stopDrawing{ CATiledLayer *tiledLayer = (CATiledLayer *)[self layer]; [tiledLayer removeFromSuperlayer]; tiledLayer.delegate = nil; } // Set the CGPDFPageRef for the view. - (void)setPage:(CGPDFPageRef)newPage { CGPDFPageRelease(self->pdfPage); self->pdfPage = CGPDFPageRetain(newPage); //self->pdfPage = newPage; } -(void)drawRect:(CGRect)r { } // Draw the CGPDFPageRef into the layer at the correct scale. -(void)drawLayer:(CALayer*)layer inContext:(CGContextRef)context { // First fill the background with white. CGContextSetRGBFillColor(context, 1.0,1.0,1.0,1.0); CGContextFillRect(context,self.bounds); CGContextSaveGState(context); // Flip the context so that the PDF page is rendered // right side up. CGContextTranslateCTM(context, 0.0, self.bounds.size.height); CGContextScaleCTM(context, 1.0, -1.0); // Scale the context so that the PDF page is rendered // at the correct size for the zoom level. CGContextScaleCTM(context, myScale,myScale); CGContextDrawPDFPage(context, pdfPage); CGContextRestoreGState(context); } // Clean up. - (void)dealloc { CGPDFPageRelease(pdfPage); [super dealloc]; } </code></pre> <p>And this is where i try to stop and release PDF in view controller: <code>v</code> is instance of <code>TiledPDFView</code></p> <pre><code> -(void) stopDwaring { [v stopDrawing]; [v removeFromSuperview]; [v release]; [self.view removeFromSuperview]; self.view = nil; CGPDFDocumentRelease(pdf); } </code></pre>

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